The present invention relates to sprinkler units and pertains particularly to an improved sprinkler unit having an adjustable orifice for adjusting the arc of coverage around the sprinkler unit.
Sprinkler units are quite extensively used for the application of water to lawns and agricultural plants. Many forms of sprinkler units are available which provide various degrees of coverage of particular areas. Typically sprinkler units are constructed to provide a fan-type pattern of spray out from the sprinkler unit. The pattern typically covers various segments of a circle and sprinkler heads are specifically constructed to provide the particular angle of coverage.
This prior art approach, however, requires that a different sprinkler head be constructed for each spray pattern. This is expensive not only in requiring a separate production line for each sprinkler head but also requiring maintenance of inventory and shipment of different heads for each requirement.
It is therefore desirable that a single sprinkler head unit be available that is selectively adjustable to provide a selective area of coverage as well as an adjustable flow rate.